Post operative knee brace

ABSTRACT

An orthopaedic brace having a pair of arms to be secured to wearer&#39;s body. There is a pivotable joint between the arms to allow pivoting of the knee while supporting the knee. According to the invention there is a joint in the brace to allow controlled inclination of each arm relative to the pivotable joint. A method of bracing a knee following high tibial osteotomy is also disclosed. According to the method aspect the brace as described above is located about the knee and the arms are adjusted to allow controlled inclination of each arm relative to the pivotable joint to provide the required bracing of the required inclination.

FIELD OF THE INVENTION

This invention relates to an orthopaedic brace and to a method ofbracing a knee using that brace.

DESCRIPTION OF THE PRIOR ART

U.S. patent application Ser. No. 934,819 filed Aug. 24, 1992, which is acontinuation-in-part of application Ser. No. 697,146 filed May 8, 1991,teaches a method of reducing the effects of unicompartmentalosteoarthritis of the knee. The method comprises applying a force to theknee as the knee moves to extension. The force is applied on that sideof the knee remote from the compartment having osteoarthritis. The forceis applied at about 10° to 15° posterior of the normal axis of rotationof the knee.

This method has attracted considerable interest and has achievedexcellent results. It is a non-invasive treatment of uni-compartmentalosteoarthritis. This complaint, which may occur in the medialcompartment or in the lateral compartment of the knee, is a malfunctionof the knee where uneven distribution of pressure occurs across theknee. This produces excessive wear on the inside of the knee joint inmedial compartmental osteoarthritis and on the outside of the knee jointin lateral compartmental osteoarthritis. A healthy knee joint has aneven distribution of pressure medially and laterally and the spacebetween the femur, or thigh bone, and the tibia, or shin bone, issymmetrical and approximately one quarter inch. If uni-compartmentalosteoarthritis is induced, for example by injury or by aging, the spacebetween the femur and the tibia decreases. The problem may progress tothe extent that the space is eliminated and the femur contacts thetibia. Erosion of the tibia may then result.

With the disease there is a change in the normal angle between the femurand tibia. For example if the patient stands in 2° of varus, orbow-leggedness, then with the advancement of the disease the angle willincrease to, for example, about 5° varus. Debilitation of the knee willcontinue and the angle is increased further.

Prior to the development of the above method of the above United Statespatent application, uni-compartmental joint disease was treated in threeways:

1. Anti-inflammatory and analgesic compounds:

2. High tibial osteotomy: and

3. Total knee arthroplasty (TKA) or knee replacement.

High tibial osteotomy involves the removal of a triangular segment ofthe tibia as a means of correcting the excessive inclination induced byuni-compartmental osteoarthritis. After surgery the knee is encased in acast that immobilizes the knee.

U.S. Pat. No. 3,902,482 issued Sep. 2, 1975 relates to an orthopaedicbrace having portions attachable to parts of a wearer's body on oppositesides of a body joint. There is a mechanical joint comprising a bearingplate on an end of each brace portion near the body joint. A linkextends across the body joint and has a bearing plate on each end. Thebearing plates of the link overlap the bearing plates of the braceportion to provide dual bearings. A pivot interconnects the bearingplates of each of the dual bearings. The pivot provides each of the dualbearings with a plurality of transverse pivotal axes, which areshiftable to accommodate the natural pivotal movement of the body joint.This arrangement is such that one of the brace portions is movable awayfrom and toward the other of the brace portions as the body joint isflexed and straightened.

Braces of this type have achieved excellent acceptance. They are usuallycustom made for a patient. They are light and unobtrusive to wear.Although the pivot is light and seemingly simple in construction, it hasexcellent ability to follow the relatively complex motion of the knee,unlike the braces that preceded it.

Since the above United States patent issued a substantial number ofsophisticated orthopaedic braces have come onto the market.

SUMMARY OF THE INVENTION

The present invention seeks to use a brace of the type generallydescribed and claimed in U.S. Pat. No. 3,902,482 modified to be usefulas a post-operative brace after a patient has had high tibial osteotomy.

Accordingly, and in a first aspect, the present invention provides anorthopaedic brace comprising a pair of first arms to be secured to awearer's body, a pivotable joint between said first arms to allowpivoting of the knee while supporting the knee, the improvementcomprising, a joint in the brace to allow controlled inclination of eachfirst arm relative to the pivotable joint.

In a further aspect, the invention is a method of bracing the knee of apatient following high tibial osteotomy comprising locating a brace, asdiscussed above, about the knee, following surgery, and adjusting theinclination of the arms of the brace to provide the required bracing atthe required inclination.

DESCRIPTION OF THE DRAWINGS

The invention is illustrated in the drawings in which:

FIG. 1 is a front view showing part of a brace according to the presentinvention in position on a leg of a patient;

FIG. 2 is a front view of a brace according to this invention;

FIG. 3 is a side elevation of the brace of FIG. 2;

FIG. 4 is a front view of a further embodiment of a brace according tothe present invention;

FIG. 5 is a side elevation of the brace of FIG. 4, partially in section;

FIG. 6 is a front view of a part of a brace according to the presentinvention;

FIG. 7 is a side elevation of the brace of FIG. 6, partially in section;

FIG. 8 is a front view of a further embodiment of the present invention;

FIG. 9 is a side elevation of the brace of FIG. 10; partially insection;

FIG. 10 is a detail of the brace of FIGS. 8 and 9; and

FIGS. 11 to 13 illustrate the method according to the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

First, in the interest of clarity the various straps and supports usedto locate the brace on the leg and, in certain circumstances, to applypressure to the leg are not shown in the drawings. They do not form afeature of the present invention but are wholly within the prior art.

The drawings show a brace having an upper cuff 10 and a lower cuff 12.The upper cuff 10 fits around the thigh 14 of a wearer and the lowercuff 12 around the upper calf 16.

Cuff 10 is attached to a first arm 18 and located by screws extendingthrough the cuff 10 to engage in threaded openings 20 in the arm 18--seeFIG. 2. A second arm 22 is attached to cuff 12 in the same manner. Thebrace of the present invention is secured to a wearer's body by use ofthe cuffs 10 and 12. There is a pivotable joint 24 between the arms 20and 22 that allows pivoting of the knee even when the brace is present.Although it does not form a feature of the present invention, thepivotable joint 24 comprises, as shown most clearly in FIG. 3, an innerbearing plate 26 comprising two part spherical projections 28. Thesepart spherical projections 28 each engage within a correspondinglyshaped bearing plate 30 and 31 on the end of each arm 18 and 22. Thesebearing plates 30 and 31 are, in turn, received within an outer bearingplate 32 again comprising, like the inner bearing plate 26, two partspherical members 34 that are a close fit over the bearing plates 30 and31 on the end of the arms 18 and 22.

Bearing plates 30 and 31 each have slots 36 formed in them engaged by abolt 38 extending through a clear hole (not shown) in the outer plate 32to engage a threaded hole (not shown) in the inner plate 26. Pivotpoints are each defined by a second bolt 40 extending through a clearopening in the outer plate 32, through a clear opening in a bearingplate 30 or 31 to engage a threaded opening in the inner plate 26. Theinner plate 26 is shown with an opening 42 that receives a strap, thatis not shown and is not part of the present invention.

According to the invention the embodiment of FIGS. 2 and 3 has a joint44 in each arm 18 and 22. The joint 44 allows controlled inclination ofeach arm 18 or 22 relative to the pivotable joint 24. In the illustratedembodiment the joint 44 in each arm 18 or 22 is formed close to thepivotable joint 24 of the brace. Each arm 18 or 22 is formed in at leasttwo parts. A first part 46 extends along the leg of the wearer, as shownparticularly in FIG. 1 and a second part 48 extends from the bearingplates 30 or 31.

There is a tab 50 on each first part 46. Tab 50 has a threaded opening52 that receives a screw 54. There is an opening 56 in each second part48 that receives a tab 50 and there are means to secure the first andsecond parts 46 and 48 together and to lock them in a predeterminedposition. Screws 54 provide means to move the first and second parts 46and 48 relative to each other to set the predetermined position.

As shown in FIG. 3, the means to secure the parts 46 and 48 and to lockthe parts in a predetermined position comprises a clear opening 58 ineach second part 48, adjacent the opening 56 through which the tab 50extends. There is a threaded opening 60 in the first part 46 thatreceives a screw 62.

The brace of FIGS. 2 and 3 is used as follows.

Prior to surgery the patient will be fitted with a brace according toFIGS. 2 and 3, custom made as is usual with this type of brace. That isto say the cuffs 10 and 12, in particular, will be moulded to match thepatient's leg. In addition, the arms 18 and 22 will be of theappropriate length for the patient and will ensure that the pivotaljoint 24 is in the proper position relative to the patient's knee.

After the operation the surgeon will adjust the brace in precisely thecorrect manner for that patient to ensure that the correct adjustment isapplied to support the knee following surgery. The surgeon can applyvarus, that is bow-leggedness, or valgus, that is knock-kneedness, asdeemed fit.

The appropriate setting is achieved in the following way.

First, the screws 62 are loosened which means that the first part 46 ofeach arm can move relative to the second part 48 of the arm. The screws54 may also be slackened if necessary. Once the screws 62 are loose, thebrace is placed on the leg of the patient. The screws 54 are tightenedin openings 54 until it makes contact with the part 48 of the arm 18 and22. When the surgeon is satisfied that the correct position isestablished in this way, the screws 62 will be tightened to secure thatposition. FIG. 3 illustrates slackening of the top screw 62 so that itis in a position in which part 46 can be adjusted, as shown by thebroken lines in FIG. 3. FIG. 3 also shows, at the bottom, a correctlyadjusted brace, that is both the screws 54 and 62 are tightened.

FIGS. 4 and 5 illustrate a further embodiment of the invention in whichcontrolled inclination of each arm relative to the pivotable joint isachieved by a hinge 64 formed in the pivotable joint.

Many details of the embodiment of FIGS. 4 and 5 are the same as in FIGS.1 to 3 and, accordingly, the same reference numerals are used asappropriate. No further discussion of these features is included.

However, FIGS. 4 and 5 shows a pivotable joint 24 formed in two parts, afirst 66 and a second part 68. The hinge 64 is also formed in two parts,with one part 70 attached to the first part 66 of the pivotable jointand the second part 72 attached to the second part 68 of the pivotablejoint. The second part 72 is formed with an internal thread. There is athreaded hinge pin 74, extending through the first and second parts 70and 72 and engaging the thread in the second part 72. The arrangement issuch that slackening and tightening of the pin 74 in the threaded part72 allows setting then locking of the brace in a predetermined positionwith the arms 18 and 22 at a controlled inclination to the pivotablejoint 24. Parts 70 and 72 of the hinge have abutting internal surface at76 and, instead of relying on contact of flat internal surfaces, FIGS. 4shows the formation of mutually engagable serrations at 76 to assistlocking at the predetermined position.

To use the brace of FIGS. 4 and 5, the same general procedure isfollowed as discussed for the embodiment of FIGS. 2 and 3 but adjustmentof the relative positions of the arms 18 and 22 is achieved by looseningthe hinge pin 74, moving the internal surfaces of the hinge parts 70 and72 away from each other and inclining the arms 18 and 22 using theserrations at 76 which, typically, are precisely machined. When theappropriate setting is fixed the hinge pin 74 is tightened in positionin the second part 72 to fix the setting.

The embodiment of FIGS. 6 and 7 may be considered a combination of theembodiment of FIGS. 2 and 3 and the embodiment of FIGS. 4 and 5 in thatthere is a joint in each arm, as in FIGS. 2 and 3, but that joint is ahinge, as in FIG. 3, 4 and 5. Again, as appropriate, the same referencenumerals are used, the hinges being described as for FIG. 4. Use of thisembodiment is as for FIGS. 4 and 5 except that each hinge 64 is set bythe surgeon as appropriate.

The embodiment of FIGS. 8 to 10 may be considered a combination of allthe preceding embodiments. There are hinged joints 64 in each arm 18 and22 but adjustment of the joints 64 is not achieved by threading of thehinge pins 74 but by the use of screws, as in the embodiment of FIGS. 2and 3. Hinge pins 74 need not be threaded although it is a convenientway of ensuring that they remain in position in the brace. In the braceof FIGS. 8 to 10 there is a tab 78 extending from the second part 48,over the first part 46 of each leg. As in FIGS. 2 and 3 there is athreaded opening 60 in each first part 46 that receives a screw 62extending through a clear opening 58 in the tab 78. There is a threadedopening 80 in the tab 78 and the screw 54 extends through that threadedopening 80 to abut the first part 46. Control of the inclination usingthese screws is as for the embodiment of FIGS. 2 and 3.

The following experimental procedure illustrates the use of a braceaccording to FIGS. 2 and 3.

The patient was a female, 50 years old with persistent medial knee pain.Previous diagnosis had showed the presence of medial osteoarthritis.More recent radio-graphs had showed marked medial joint narrowing. Thefemur and tibia were about at 180°. It was decided to correct by about5°.

The patient was given a spinal anaesthetic and positioned on her leftside with a lateral aspect of her right leg facing up. A tourniquet wasapplied to the leg which was draped. Using the fibular head and patellaas landmarks, an anterior to posterior incision was made about 1" belowthe joint line. A number 16 needle was then placed in the joint line toserve as a further landmark. Great care was taken to avoid the posterioraspect of the fibular head and all tissue and muscle was resected fromthe wedged site. A tape measure was used to mark the wedged site.

Most of the fibular head was removed, a procedure necessary to avoid thefibula holding the wedge site open. The wedge was cut free-hand using ajigsaw-type blade. The cut was carried out medially until the bladecontacted the cortex. It is desirable not to cut all the way across thetibia. The bone was tidied using standard surgical instruments and thefit of the bone was checked by applying valgus stress to the leg. Theleg was elevated at the foot so that gravity applied the valgus stressto the bone.

A stepped staple was hammered in to hold the wedge closed. A secondstaple with no step was also applied slightly posterior of the first.The wound was cleaned and the incision closed. A dressing was applied tothe incision site.

In a conventional procedure a web roll would be applied as an underlayfor a synthetic cast. With the leg still elevated for valgus stress, tworolls of 5 inch synthetic casting material would be applied to form ashort leg cast with 20° of flexion. In these circumstances, the kneewould be kept in the cast for four to six weeks. The cast could bechanged if it becomes too loose but the knee would be immobilized.

According to the present invention, a brace would have been fitted tothe patient prior to the operation. In those circumstances, subsequentto the application of the dressing, the brace would be refitted to thepatient and adjusted by the surgeon using the procedure described above,that is screws 54 and 62 would be loosened and tightened as appropriateuntil the surgeon's satisfaction to achieve bracing of the knee withoutimmobilizing of the knee. Adjustment of the brace can be carried outwith extreme ease at any time, at the surgeon's discretion.

FIGS. 11 to 13 illustrate the various steps in the method according tothe present invention. The brace generally illustrated in these drawingsis the brace of FIG. 2 and 3.

FIG. 11 shows the leg prior to the operation. The brace is fittedaccurately. In particular it will be noted that cuffs 10 and 12 fit thethigh and calf of the patient respectfully. Screws 54 and 62 areadjusted to ensure that that position is properly established.

FIGS. 12 and 13 show the leg after high tibial osteotomy. In FIG. 12 thebrace is adjusted as in FIG. 11. That is the brace is as fitted to theleg prior to the osteotomy. Because of the wedge removed, cuff 12 nolonger fits properly. Note in particular the gap 13. As a result thebrace is adjusted, as described above, so that the cuff 12 and the cuff10 both fit properly and the gap 13 is eliminated. This arrangement isshown in FIG. 13.

The embodiment of FIGS. 2 and 3 is generally illustrated in FIGS. 11 to13 but precisely the same considerations apply in all other embodimentsof the invention.

Using the present invention, the knee is not immobilized as it would bewith a cast. The knee can move while fully supported. However, the kneeis also securely braced. The degree of movement of the knee can becontrolled in a manner known with braces of the sort illustrated in thedrawings.

Adjustment of the relative inclination of the cuffs to the pivot caneasily be carried out.

I claim:
 1. In an orthopaedic brace comprising:a pair of arms to be secured to a wearer's body, a pivotable joint between said arms to allow pivoting of the knee while supporting the knee, the improvement comprising: joint means in the brace for allowing controlled medial and lateral inclination of each arm relative to the pivotable joint.
 2. A brace as claimed in claim 1 in which there is a joint means in each arm, formed adjacent the pivotable joint of the brace.
 3. A brace as claimed in claim 2 in which each arm is formed in at least two parts, a first part and a second part:a tab on the first part; and an opening in the second part to receive the tab; means to secure the first and second parts together and to lock them in a predetermined position; and means to move the first and second parts relative to each other to set the predetermined position.
 4. A brace as claimed in claim 3 having a threaded opening in the tab;a screw to extend through the threaded opening to abut said second part of the arm; whereby turning of the screw to move it into the threaded opening acts to separate said tab and said second part of the arm.
 5. A brace as claimed in claim 3 in which the means to secure the parts and to lock the parts in a predetermined position comprises a clear opening adjacent the opening in said second part and a threaded opening in said first part, tightening of the screw into the threaded opening acting to lock the first and second parts of the arm together.
 6. A brace as claimed in claim 1 in which the joint means to allow controlled inclination of each arm relative to the pivotable joint comprises a hinge formed in the pivotable joint.
 7. A brace as claimed in claim 6 in which the pivotable joint is formed in a first and a second part, the hinge being formed in two parts, one part attached to the first part of the pivotable joint and a second part attached to the second part of the pivotable joint:at least one of said parts of the hinge being internally threaded; a threaded hinge pin extending through the first and second parts, slackening and tightening of the pin in the threaded part allowing setting and locking to control the inclination of each arm relative to the pivotable joint.
 8. A brace as claimed in claim 7 in which the first and second parts of the hinge abut each other at internal surfaces;mutually engagable serrations at the internal faces to assist locking at a predetermined position.
 9. A brace as claimed in claim 2 in which the joint means in each arm is a hinge.
 10. A brace as claimed in claim 9 in which each arm is formed in at least two parts, a first part and a second part;each hinge being formed in two parts with a first part of the hinge attached to the first part of each arm and a second part of each hinge attached to a second part of each arm; means to secure the first and second parts together and to lock them in a predetermined position.
 11. A brace as claimed in claim 10 in which the means to secure the first and second parts together comprises at least one of said hinge parts being threaded;a threaded hinge pin extending through the first and second parts of the hinge whereby slackening and tightening of the pin in the threaded part of the hinge allows setting and locking of the first and second parts of each arm relative to each other to set the predetermined position.
 12. A brace as claimed in claim 10 in which the first and second parts of each hinge abut each other at internal faces;mutually engagable serrations at the internal faces to assist locking at the predetermined position.
 13. A brace as claimed in claim 10 in which the means to secure the first and second parts of each arm together and to lock them in a predetermined position comprises a tab on the first part extending over the second part;means to secure the first and second parts together and to lock them in a predetermined position; and means to move the first and second parts relative to each other to set the predetermined position.
 14. A brace as claimed in claim 13 in which there is a threaded opening in the tab;a screw to extend through the threaded opening to abut said second part of the arm; whereby turning of the screw to move it into the threaded opening acts to separate said tab and said second part of the arm.
 15. A brace as claimed in claim 13 in which the means to secure the parts and to lock the part in a predetermined position comprises a clear opening in said second part and a threaded opening in said first part, tightening of the screw into the threaded opening acting to lock the first and second parts of the arm together.
 16. A method of bracing a knee of a patient following high tibial osteotomy comprising:locating a brace about the knee, said brace having a pair of arms to contact the leg of the patient and a pivotable joint between said arms to allow pivoting of the knee while supporting the knee, a joint in the brace to allow controlled medial and lateral inclination of each arm relative to a pivotable joint; and adjusting the inclination to provide the required bracing at the required inclination.
 17. A method as claimed in claim 16 including locking the inclination once the desired adjustment has been achieved. 